


If You Impregnate Me, Our Baby Can Save Our Sister

by HomerSoc



Category: Original Work
Genre: Brother/Sister Incest, F/M, HomerSoc, Impregnation, Incest, Sibling Incest, Virginity, gwa, reluctance, script offer
Language: English
Status: Completed
Published: 2021-01-18
Updated: 2021-01-18
Packaged: 2021-03-17 03:08:51
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,804
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/28842141
Author URL: https://archiveofourown.org/users/HomerSoc/pseuds/HomerSoc
Summary: The little sister to two fraternal twins is dying, and only stem cells from a closely related baby's umbilical cord can save her life. But their parents haven't had any luck in having another child, despite their desperation. That's when the twins realize it's not just their parents that can make the baby that will save their sister.
Comments: 1
Kudos: 19





	If You Impregnate Me, Our Baby Can Save Our Sister

So, I guess you heard. Mom still isn’t pregnant yet.

It’s weird. She and dad had the two of us so easily. You know the story. She and dad wanted a big family. When her first pregnancy was twins, she thought that was the beginning of the dream coming true.

But then it took her and dad almost ten more years to have our sister. 

They kept trying, of course. [laugh] We used to joke about how loudly they’d try then we were younger. Back then all that was at stake was having another kid.

But now, they need to have one to save our sister.

One more baby. That’s all that’s needed. Then they can use the umbilical cord blood to cure our sister. But it’s not just happening. And you’ve seen our sister. She just keeps getting sicker and sicker. They say she has a year left. Maybe two.

They still could find a match. But there’s so many ways the blood needs to match, and it has to be umbilical cord blood. Our cousin offered when she had her baby, but she wasn’t a close enough match.

I feel so helpless. Our sister is dying. The stress is just destroying mom and dad. It’s definitely not good for you and me. But there’s nothing I can do.

Well, I guess there is.

I thought about getting pregnant. I’m her sister, so I’m pretty close genetically to her. Of course, that all goes out the window is I get impregnated by some random guy.

But, um… if I were knocked up by someone with very similar genetics to me. Like, say my brother…

[pause for reply]

Yes, I am suggesting that. 

But just think about it. It’s our last hope to save our sister. The odds of mom and dad having a baby at this point is next to nothing. Even if they didn’t have trouble conceiving in the first place, their ages make it more and more difficult. But we’re young. We are already perfect matches for our sister. They found that out when they tested us to make sure we also didn’t have the mutation that made her sick. It’s just that they need umbilical cord blood for the cure. We could provide that. 

At least our baby could.

Yeah, I know Mom and Dad would freak out if they knew we had sex. If we were to go up to them and suggest it, they would tell us no. Not even to save our sister. At least I think they would. They’re so desperate now that I could be wrong.

We can’t take that chance though. There’s that saying. “It’s easier to beg forgiveness than to ask permission.” They don’t even need to know unless I get pregnant. Then we tell them, and they freak out at first. And then they realize that this is the miracle they were praying for.

They’ll forgive us. Maybe it changes what they think of us. Maybe the doctors look at us weird when they find out what happened. But does any of that matter if it saves our sister?

It’s not like we’re doing this because we were horny teenagers left alone for the weekend by their parents, or one of us was making the other do it. We’re still doing something wrong, but for all the right reasons. 

I know this is all kinds of weird. We don’t think of each other in any kind of sexual way. At least, I’ve never gotten that vibe from you, and your hesitation is more than putting on a polite show of not wanting to screw your sister. We could ask the doctors about artificial insemination, but I’m pretty sure no doctor would impregnate me with my brother’s sperm. I could have you, um… provide me your sperm less directly, say in a cup or something. Then I could do the rest. But something tells me that’s not as likely to succeed as… as making a baby the old-fashioned way. And we don’t really have much time to take chances on something that’s less likely to work.

Look, I’m prepared to do anything I need to in order to convince you to impregnate me. Not for me, or for you. But for our little sister. I know you want to save her too, and you don’t want to make this any more difficult for me than it has to be. You know I can’t do this without you.

So… are we going to save our sister?

Good.

So, um. I guess we should take off our clothes.

Yes, now. We’re both here, and you just agreed to do it. But if we wait, then maybe you change your mind. Or I change my mind. Or we find a reason to keep putting it off. Time that our sister really doesn’t have. 

I’ll turn off the light in your room. This doesn’t feel like something we should be doing with the lights on.

And… that’s not as dark as I had hoped. But it’s better than before. Um, we can both turn around and look the other way as we take off our clothes. Yes, I know we’re going to have sex. But it feels wrong to get naked in front of my brother. Now, no peeking.

Um, okay. I’m not wearing any clothes now. Stay turned around, and I’ll get into your bed. Then I’ll close my eyes as you get in too. Then we can… you know. Save our little sister.

My eyes are closed. You can come over now. Um, maybe close your eyes as you get under the covers, just so you don’t see anything. Just lie beside me for now. But not too close.

Well, this is strange. I’ve never been in bed with another person before. Not even when I was younger and had sleepovers. Then it was all sleeping bags or stuff like that. But lying in bed with someone, and feeling someone else’s presence in the bed. Especially someone male. With a penis.

So… um. If you’re ready, just get on top of me I guess.

What do you mean, you’re not ready? You are going to do this, aren’t you?

[short pause]

Oh, that. Yeah, I guess it would help if you were hard first. I kind of took it for granted that you would be. Of course, I am your sister. Between that and thinking of your other sister, either of those might be a mood killer for you.

Look, don’t take this the wrong way, but I’m going to lend you a helping hand, okay? I’m just going to move my hand over to where you are. There’s your hip. If I follow it up, and then further in.

[gasp] Yep, that’s a penis all right. Sorry. It’s my first one. Well, we did share a womb together for nine months, but honestly that entire time is kind of a blur to me. I’m pretty sure it’s bigger now, too. A… a lot bigger apparently. 

I’ll wrap my fingers gently around it and stroke it. Maybe I should lend myself a hand, too, so that we’re both a little excited going into this. I mean sexually excited, and not in the general sense of being enthusiastic.

This isn’t as easy as I thought. If it was just masturbating you or masturbating me, that would be one thing. But I have to jerk your cock, which requires one kind of motion. And I have to play with my pussy, which requires a whole lot of other motions. I guess I’m going okay. You’re harder, and I’m getting a little wet. 

I can hear you breathe a little louder now. You were nervous at my touch at first. You probably haven’t had any more sexual experience than I have. In the last couple of years there hasn’t been much time for ourselves, let alone being with people that weren’t family, or doctors, or something like that. So you’re nervous, just like I am. And you can’t help thinking it’s your sister’s hand on your cock, which probably isn’t helping things. But at the same time, it seems to be becoming less of an issue the longer I jerk it for you.

It’s not easy for me either. I’m trying to play with myself and make me excited, but I know it’s my brother’s body lying next to me, and his cock in my hand. It’s almost enough to completely offset what my fingers are doing to me. Except, like you, the more successful I am, the less I think about that. 

Oh my God. Did you just cum? I feel wetness on my hand. If you just wasted your sperm in my hand, instead of inside me…

Oh. It’s pre-cum. I’ve heard of that, I guess. So… you’re still good to go? You can still… make sperm? Like, if you were to put your cock into me?

Because this might be a good time to do it.

I’m wet enough I guess. And you’re definitely hard enough. I’m worried about going too far with this masturbation thing. If you came in my hand I could try to push all of the cum into me, but I don’t think that would work all that well. We should move on to the sex thing 

I guess this is where you get on top of me. Try to do it without seeing me under the covers. It wasn’t that dark in here to begin with, and our eyes are adjusting, and I really want to maintain some modesty here. I know that doesn’t make sense, because you’re going to be inside my pussy soon. It shouldn’t matter if you see that, or my breasts. But it does.

I’ll lift up the covers just a bit so you can get on top of me without getting all tangled in the sheets. So, yeah… just get on top of me. They… they make it look easy in the movies. Regular movies, and not porn or anything. But when the guy gets on top of the girl, it’s all smooth and sexy, and not both of us trying to keep our knees from going places they shouldn’t go. It’s also hard when the feel of the other person’s naked flesh feels entirely wrong against yours. Sure, we’re both warm and soft, but part of it is knowing that we’re brother and sister.

Still… you’re on top of me now. I can look up and see your face. You look like dad, which doesn’t help. But worst of all, you look like you. No offense. You’re not bad looking. You’re just very… brotherly-looking. 

I did try closing my eyes, but they fly open every time some new part of you touches me. And not even the most important part of you yet. Maybe we should try to get that thing into me? I’m not necessarily looking forward to it, but this is just getting increasingly awkward, and we’re here to make a baby, right?

Oh. That’s a definite eye-opening moment. I can feel the head of your cock against my pussy. Sorry for flinching. I think I would have done that with any other boy. It just feels weird to have a cock that close to me down there. I’ve thought about doing this with a boy before, and of someday having a baby. I just didn’t think that the boy would be you, and that the baby would be being made that first time.

I… I guess this is where we have sex next? Followed by orgasm, and impregnation? But on the bright side, in nine months we could be saving our sister’s life. Maybe a little longer. This might not work the first time. We may have to do this a bunch of times. But don’t worry about that right now. Before there can be multiple times, there has to be a first time. And it will be easier after that first time. At least I hope so. Never easy in an absolute sense. But not as hard.

Okay. Enough talking. At least talking before we start. You know me. I’m probably going to be talking the entire time here. It’s what i do when I’m nervous, and I don’t think I’ve been this nervous before.

Like now, when you start to push it against me, and it goes in a little. Getting really, really nervous, and feeling really, really talkative. I should be quiet and let you focus, but as the head of your cock pushes its way into me… well, talking about it distracts me. Maybe not so much from the cock part, but from who the cock is attached to.

Well, this is it. I feel like I should give you one last chance to back out. I’m still a virgin, I think. I’m not sure what percentage of cock needs to be in me for it to count. We’ve already done some bad stuff together, but if you keep going, then it gets really horribly bad in a moral sense. Except we’re doing it to save our sister, so it all cancels out. Right?

So, you could stop. Or you can keep going on. But I think we can both live with what we’re about to do. What we could never forgive ourselves for is if we didn’t do anything we could to save our sister.

Well, have you decided? Are you going to fuck one sister to save the other?

I can see the answer in your eyes. I shouldn’t be looking into them. They’re way too familiar. But the alternative is to focus on the feeling of your cock trying to get into my pussy, and I don’t know what is the more uncomfortable sensation at the moment.

But if it helps you at all, look back into my eyes too. Distract yourself, and distract me. Then take me. Take my virginity, and fuck your twin sister.

[moan as entered]

Oh. The distraction didn’t work as much as I had hoped. I still felt every bit of you sliding into me. It just kept going, too. You didn’t feel that big when it was just in my hand, although it was still big. But now it’s inside me… filling me…

Well, don’t just lie there. You know, on top of me. I’m pretty sure there’s more to this sex thing than you just sticking it in me. Otherwise, we’re going to be like this all night, and I was going to help tuck in our sister in about an hour. So… move or do sex stuff in me I guess.

[soft moan] Yeah, like that. You’ve got to stimulate your cock to the point where it ejaculates in me. I was worried that you were too close before when I was masturbating you. Now, I’m wondering if maybe I should have gotten you closer. But maybe this way is better for making babies. You know, where most of the arousal is done when you’re inside of me. Maybe it tells my body to be ready to accept a big load of sperm, and be ready to put it to good use making a baby or something.

She’s going to find out someday. I just thought of that. She won’t always be the little girl she is now. Thanks to us, she’ll grow up, and get smarter. No one will tell her who made her big sister pregnant to save her, but she’ll figure it out in some moment of revelation. Then maybe she’ll get the mental image of what we’re doing right now… your naked body on top of mine… your hard cock in my soft pussy… your body moving against mine.

And our child will find out someday, too. I don’t think under the circumstances that’s a secret we can keep forever either. But all of those things are future things. Our making a baby is a now thing. Saving our sister is a soon thing. Her finding out about us, or our child figuring out who their father is… they’re all long, long away things. 

God, I keep getting wetter. That’s a good thing, right? I feel kind of ashamed because of it. By all of this really. I know it's all for a good cause. But it’s hard not to feel bad about it. Even if it starts to feel kind of good, too.

There. I said it. This isn’t too bad. They say that pizza is kind of like sex, and there’s no such thing as bad sex or bad pizza. And I don’t have any comparison, anyway. For sex, I mean. I’ve had lots of pizza. But this is my first sex. It’s weird and awkward and messy, and I can never forget who I’m doing it with. But it’s… it's not as horrible as I thought it was going to be. 

You’re going faster. That means you’re okay with it too, doesn’t it? You’ll be able to finish this, and cum in me, even if I am your sister. We wouldn’t be doing this if I weren’t. At least I don’t think so. Maybe if we weren’t brother and sister, we would have met, and wanted to do this on our own, without our sister’s life in the balance. 

[moan] Would you? Would you fuck me, even if I wasn’t your sister? Even if we didn’t need to do this to save a life? Just for… for fun. Like normal, non-related people. Maybe after a date, and after you put on a condom, and things like that.

But I am fuckable, aren’t I? I know it’s weird to say that about your sister. But it’s no as weird as actually fucking her, and we’re already doing that. So… you can tell me.

[sigh] Thanks for saying that. Like I said, neither of us gets out that much anymore. Maybe all of this should have driven us into the others arms and the other’s bed a long time ago. But that would have been wrong,even if it was for comfort. This is a selfless gesture to save our little sister. The fact that it might be somewhat enjoyable is entirely beside the point. 

Don’t feel guilty though. Not for having sex with me. Not for cumming in me. I;ll feel guilty enough for both of us. Guilt and pleasure are swirling around inside of me, trying to see who is in control. And more and more, it’s the pleasure that’s winning out. But when that goes, the guilt will return. 

But it will be worth it. If I get pregnant, we know the baby will be the right match for our sister. She’ll be saved. Will what we’re doing now, and possibly an excessive amount of times in the near future matter in comparison to that?

Oh God. It’s going to happen soon, isn’t it. We’re going to cum, and then your sperm will be in me. I’ll probably get pregnant. At least if I did my math right. I may have also borrowed some of mom’s fertility drugs, just to be safe. Mom and Dad’s problems with conceiving aren’t supposed to extend to us… not that they ever imagined we’d be trying to have a baby together. 

Please… cum in me. It’s to save our sister, so all of this is okay. It does feel okay, doesn’t it? Even if it feels really wrong, too. I may have trouble looking you in the face after this, even if I can’t stop doing that now. Especially as I see lust build in that face as you get closer and closer, just like I know it builds in mine. Until… neither of us can fight it anymore…

I’m cumming! Please, don’t make me cum alone. Then I’ll feel guiltier than ever… please cum in me…

Oh God. I can feel you cumming in me. There’s so much, and it keeps coming, just like I am. Give it all to me. I know I technically only need one lucky sperm to make a baby, but I want every last one…

[pause]

Well, that’s it then. We did it.

Just kind of lie there a bit. Just… just let your cock drain every last bit into me. I know it’s increasingly awkward for your cock to still be in me now that the passion is slowly fading, but… it’s for a good cause. 

I guess I’ll have to shower before I help tuck our sister in. I can’t have her seeing me all messed up like this, or me smelling like… well I guess this is what sex smells like. Or I might run into mom or dad, and I’d much rather delay them knowing about what we did until we know I’m pregnant. Maybe even longer. Maybe they’ll suspect, but be afraid or have the good decency not to ask. As long as it saves our sister.

There. That’s probably enough. You can get off of me now.

It’s still just as important that you don’t see me naked. I keep the covers pulled up over my breasts, even if they heaved under you and the nipples poked into your chest just a minute ago. But you were more lover then, and less brother. 

I… I should go now. I need to shower, and I’m not sure what I’m feeling right now, other than more confusion than I expected. And less guilty. Although given how guilty I was expecting, that still leaves a lot of room.

So, be a gentleman and close your eyes while I get out of your bed. I don’t want you seeing my naked, sweaty body even with you being the one making it all sweaty in the first place. I’ll grab my clothes then and dash down to the bathroom.

Now keep them closed until you hear the door shut. I’ll be back tomorrow though. As I said, after the first time it will be easier. And we need to keep doing it until we know I’m pregnant. That could be weeks, or months. 

And for what it’s worth… in those few seconds where we were cumming, I forgot everything. That you were my brother. That our sister was so sick. That she hasn’t had a normal life, and neither have we for so long, not that it is her fault. In a messed up way, that orgasm was the happiest I’ve been since this all started. So… there may be benefits to us having sex above and beyond saving our sister.

Now good night, dear brother. Between the two of us, we will save our little sister. Even if it damns us in the process. Except somehow, I think this is saving us too...


End file.
